A staged screening of registered drugs highlights remyelinating drug candidates for clinical trials

There is no treatment for the myelin loss in multiple sclerosis, ultimately resulting in the axonal degeneration that leads to the progressive phase of the disease. We established a multi-tiered platform for the sequential screening of drugs that could be repurposed as remyelinating agents. We screened a library of 2,000 compounds (mainly Food and Drug Administration (FDA)-approved compounds and natural products) for cellular metabolic activity on mouse oligodendrocyte precursors (OPC), identifying 42 molecules with significant stimulating effects. We then characterized the effects of these compounds on OPC proliferation and differentiation in mouse glial cultures, and on myelination and remyelination in organotypic cultures. Three molecules, edaravone, 5-methyl-7-methoxyisoflavone and lovastatin, gave positive results in all screening tiers. We validated the results by retesting independent stocks of the compounds, analyzing their purity, and performing dose-response curves. To identify the chemical features that may be modified to enhance the compounds' activity, we tested chemical analogs and identified, for edaravone, the functional groups that may be essential for its activity. Among the selected remyelinating candidates, edaravone appears to be of strong interest, also considering that this drug has been approved as a neuroprotective agent for acute ischemic stroke and amyotrophic lateral sclerosis in Japan

Plasma biomarker profile and clinical correlations in adult patients with tuberous sclerosis complex

Background and objectives: Different pathophysiological mechanisms, especially involving astrocytes, could contribute to Tuberous Sclerosis Complex (TSC). We assessed neurodegeneration and astrocytopathy plasma biomarkers in TSC adult patients to define TSC biomarker profile and investigate clinical-radiological correlations. Methods: TSC patients≥15 years followed at Policlinico "Umberto I" of Rome were consecutively enrolled (July 2021-June 2022). The plasma levels of the following biomarkers were compared between patients and age/sex-matched healthy controls (HC): tTau, pTau181, Abeta40, Abeta42, Neurofilament Light Chain, Glial Fibrillary Acid Protein (GFAP). Results: Thirty-one patients (20 females/11 males; median age 30 years, IQR 24-47) and 38 HC were enrolled. Only GFAP was significantly higher in the whole TSC population than in HC [132.71 (86.14-231.06) vs 44.80 (32.87-66.76) pg/mL, p<0.001], regardless of genotype. GFAP correlated with the disease clinical (ρ=0.498, p=0.005) and radiological severity (ρ=0.417, p=0.001). It was significantly higher in patients with epileptic spasms [254.50 (137.54-432.96) vs 86.92 (47.09-112.76) pg/mL, p<0.0001], moderate-severe intellectual disability [200.80 (78.40-427.6) vs 105.08 (46.80-152.58) pg/mL, p=0.040] and autism spectrum disorder [306.26 (159.07-584.47) vs 109.34 (72.56-152.08) pg/mL, p=0.021]. Discussion: Our exploratory study documented a significant increase of GFAP plasma concentration in TSC adult patients, correlated with their neurological severity, supporting the central role of astrocytopathy in TSC pathophysiology